The invention relates to a driver assistance system in a motor vehicle and, more particularly, to a driver assistance system having an electronically controllable braking system and a control unit which is assigned to the braking system and is connected with an operating element also assigned to the braking system.
The known “SmartSenior—Intelligente Dienstleistungen für Senioren” (“SmartSenior—Intelligent Services for Seniors”) research project is a research initiative that aims at making life easier and safer as people age. This includes emergency recognition and driving (driver) assistance systems that are independent of the location and also promote a feeling of safety in seniors on the road.
Older people with temporary heart or circulation problems frequently are no longer confident that they can drive their own vehicle. The reason is the fear that they may no longer be able to control their vehicle as a result of heart or circulation problems and may therefore cause a serious accident. This leads to a relinquishing of individual mobility and therefore, mainly in rural areas, to a loss of a considerable amount of self-determination and to a poorer quality of life. Often, this also applies to other groups of persons with certain health-related restrictions. It is therefore a design goal to completely avoid health-related losses of control—or to at least reduce the severity of accidents due to such loss of control.
Currently, an emergency driving (driver) assistance system (emergency stopping assistant) is therefore being developed which, when a health-related emergency situation involving the driver is detected, automatically changes into an autonomous driving mode and carries out a safeguarded emergency stopping maneuver. In simple terms: the car maneuvers to the side of the road in a controlled manner as a function of the surrounding traffic and then stops. Simultaneously, an emergency call is placed with attached relevant data for the initiation of the necessary medical and traffic-related rescue measures, and efficient emergency care is thereby made possible.
The emergency stopping assistant is based on sensors for monitoring vital data, along with the already existing driver assistant systems. For example, BMW® has been offering an emergency call function for as long as ten years. In addition to the exact position determination and information concerning the vehicle, the emergency call has, since the Spring of 2007, also contained information concerning the accident. Thus, helpers not only learn the exact location and can identify the vehicle but, for the purpose of assisting, are also provided with information concerning the number of occupants and the seriousness of injuries. An intelligent algorithm computes this information from the sensor data of the passive safety system (airbags, belts, etc.). By way of this networked technology, vital data can also be forwarded to a rescue management station. The determination of valid vital data is also handled within the “SmartSenior” Project. Driving (driver) assistance systems, such as the lane change warning system or the active speed control with a stop-and-go function, form a further technological basis for the development of the emergency stopping assistant.
In addition to the clarification of prevailing legal conditions, new algorithms have to be developed in a first step for the detection and interpretation of the vehicle surroundings. In this case, special emphasis is on a reliable localization of the vehicle within its own driving lane by the fusion of redundant sensors, the recognition of the objects around the vehicle and the development of an electronic coordinator which, in an emergency, instead of the driver, makes all driving-strategic decisions and forwards these decisions to the corresponding interfaces for the longitudinal and lateral control of the vehicle.
The so-called emergency stopping assistant first has to be able to recognize a health-related emergency on the part of the driver. It is only when an emergency has been recognized by way of the analysis of so-called vital data that the car is changed to an autonomous driving mode and carries out an emergency stopping maneuver. The reliable detection and correct analysis of the vital data have proven to be extremely difficult when implementing the project in the vehicle.
There is therefore needed an improved driver assistance system of the above-mentioned type.
According to the invention, this and other needs are met by a driver assistance system in a motor vehicle and, more particularly, to a driver assistance system having an electronically controllable braking system and a control unit which is assigned to the braking system and is connected with an operating element also assigned to the braking system. The operating element, when correspondingly actuated, can initiate an automatic braking function in the form of a normal braking by use of the electronically controllable braking system independently of the actuation of the brake pedal. The control unit is operatively configured such that, when the operating element is continuously actuated beyond a predefined minimum duration, an emergency braking function can be initiated.
The invention is based on the following considerations, recognitions and ideas.
Most BMW® vehicles do not have an installed mechanical handbrake. In this case, the function of the handbrake is taken over by an electronically controlled electromechanical parking brake (EMF). By pulling an operating element in the form of an actuator in the center console, the vehicle is braked to a standstill in a controlled manner. This can also be implemented by an interaction with a hydraulic electronically controllable braking system.
An operating element (for example, an actuator or a key that can be moved into one or more positions), which is assigned to a braking system and by which at least a normal braking can be initiated by means of the given operating mode, is therefore basically part of the invention.
The use of camera systems and electric adjusting motors in the steering system (EPS), as currently already installed in series-produced vehicles, makes it possible to guide/keep the vehicle within its own lane by automatic steering interventions (tracking systems, heading control).
If, in an emergency situation, for example, a health-related inability to drive of the person steering the vehicle, the handbrake function (EMF) is triggered by the front passenger, then the vehicle will in fact reduce its speed and brake to a standstill. However, there is a possibility that the vehicle may leave the road or its own driving lane on expressways. Furthermore, in such a situation, the driver may block the gas pedal with his foot and/or block the steering wheel with his body. This may lead to accidents.
As initially mentioned, camera systems and electric steering systems for tracking systems are already being installed in current series-produced vehicles. This permits a narrow and strong guidance of the vehicle within the current driving lane.
According to the invention, the braking function is expanded by way of the operating element (accommodated, for example, in the center console) which, in particular can be manually operated also by the front passenger, and in an advantageous further development, can be combined with an automated tracking system. As a result, particularly the front passenger is enabled to intervene himself in the event of the driver's suddenly occurring inability to drive.
In a further development, the tracking system can be expanded in the direction of an autonomous driving, as in the case of the known emergency stopping assistant, so that the vehicle can be changed fully autonomously into a secure condition while taking into account the other traffic participants (for example: 1. Staying in the lane; 2. Changing the lane; 3. Stopping on the hard shoulder; 4. Sending the emergency call) as long as the operating element is continuously actuated (by the front passenger) in a predefined manner.
In contrast to the known emergency stopping assistants, emergency driver assistance functions in a simplifying manner are not activated by analyzing vital data but as a function of a manual triggering of an operating element by the front passenger.
Serious accidents can thereby be avoided. Such an assistance system also provides an insecure driver with the certainty that, if necessary, the front passenger could safely stop the vehicle.
Accordingly, the driver assistance system according to the invention is based on an electronically controllable braking system and a control unit assigned to this braking system, which control unit is connected with an operating element also assigned to the braking system. By a corresponding actuation of the operating element, an automatic braking function can be initiated in the form of a normal braking by use of the electronically controllable braking system independently of the actuation of the brake pedal. According to the invention, the control unit is further developed, particularly by a corresponding software programming, such that, when the operating element is continuously actuated beyond a (first) predefined minimum duration, an emergency braking function can be initiated.
The emergency braking function preferably includes a deceleration that is intensified in comparison to a normal braking and/or an automatic switching-on of the emergency flasher system, for example, in the form of graded emergency measures as a function of the duration of the actuation of the operating element.
In a further development of the driver assistance system according to the invention, the vehicle has a tracking system, and the emergency braking system activates this tracking system. Tracking systems are known per se.
An intensified deceleration within the scope of the emergency braking function preferably takes place as a function of a simultaneous actuation of the gas pedal. For example, the intensified deceleration can be defined to a greater degree if the gas pedal is actuated than if the gas pedal is not actuated, because it can then be assumed that it is highly probable that the driver is unable to drive and is blocking the gas pedal with his foot. In this case, the position of the gas pedal as the desired-performance element will be ignored.
The emergency braking function may also include the initiation of a (known) emergency stopping assistance function independently of the driver's vital data, for example, after a preceding intensified deceleration for a defined period of time.
The emergency braking function may also include the activation of a belt tightener function at the driver's seat and/or an adjustment of the driver's seat into the rearward end position. The belt tightener function is preferably activated first and, in the event of a still longer actuation of the operating element beyond a second predefined minimum duration, the driver's seat is then moved into the rearward end position in order to, if necessary, eliminate the blockage of the steering wheel by the driver's upper body.
A continuous actuation of the operating element may also exist if, after a brief release, the operating element is actuated again. In this case, “brief” indicates a range of seconds during which the front passenger may accidentally slide off the operating element, for example, because of nervousness.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.